This compressor speeds up and slows down constantly when above idle. Does not run at a happy speed. This was a unit I restored and best I remember it was not doing that before. I have 2 identical units. The one is fine but not this one. I have swapped the regulator that sits on top of the oil air tank and still has the same issue. Also rebuilt another air inlet valve and same problem.I have spoken to atlas copco tech support and we have not figured this one out. It makes air just fine but it should run steady but does not. I am lost at this point as to where to look. And I also put a ball valve in at the air control line that goes to the throttle control. When I close the valve it runs steady. That leads me to think the engine governor is fine. Any help would be
appreciated.
appreciated.